A day in the evolution of Lemar Marshall from an uncertain spare part two years ago to a force on the Washington Redskins' defense goes something like last Thursday: Sit in meetings at Redskins Park and study. Lift weights. Eat lunch. To the delight of your coach, get into a fight with a teammate on the practice field.

Afterward, take questions from teammates about defensive assignments and alignments.

Marshall, who turns 29 Saturday but is only in his second year as a starter at linebacker, has accomplished something that had never been forecast for him. He has emerged as not just the most productive member of the Redskins' defense but as its quarterback, the man assistant head coach-defense Gregg Williams relies on to communicate with the unit's 10 other players and act, in effect, as his alter ego on the field.

Marshall says he has something to prove to the three teams that told him he wasn't good enough. He wants to show that not only can he be a reliable, every down starter in the NFL, but one who, in his first year as a middle linebacker after Antonio Pierce left for the New York Giants, can gain the trust of Williams, one of the league's most demanding coaches.

"I didn't know when I was going to get my chance," Marshall said. "For a long time, I just knew I had to be better. I had to hear a lot of things about how I should be playing, but there was always someone else playing ahead of me. But I knew my ability. This has been a learning experience for me. I try not to think about the higher sums of money I could have made. But I think it's better to start off on a lower note and finish higher than the other way around."

The arc of Marshall's career is a study of perseverance in the intensely competitive world of the NFL. It began with deep disappointment and resentment and was resurrected under a system in which Redskins defensive coaches have helped Marshall process the slights and anger from the past and channel them in a positive direction. Marshall leads the Redskins in tackles this year, with 103, 81 of them solo. He's started every game, and is the only Redskin to score a defensive touchdown.

"You're looking at a guy who went from someone we used as a replacement to a guy who you leaned on," said Greg Blache, the team's defensive coordinator. "As good as he was last season, he's that much better this year. What he is next season should be better than this year. This isn't the last step for him."

Marshall, who played college ball at Michigan State, was not drafted in 1999. He spent time with Tampa Bay, Philadelphia, and Denver before joining the Redskins as a free agent in 2002. Steve Spurrier, Washington's head coach at the time, seemed to hold him in low regard, Marshall said.

When Williams took over the defense under Coach Joe Gibbs in 2004, he had something of an epiphany during training camp that summer. Overwhelmed by opinions about players on whom he did not have much firsthand knowledge, Williams decided he would no longer look at scouting reports, both internal and external. The slate was going to be clean. Players were no longer going to be judged on reputation or status.

It did not matter, Williams said, if a player was the fifth pick in the draft like Sean Taylor, a big-money free agent like Shawn Springs, hugely popular like LaVar Arrington, or an undrafted defensive back-turned linebacker like Lemar Marshall.

For Marshall, Williams's approach was energizing, for he had long believed that not being drafted had hurt him.

"It got tiring, always having to listen to your teammates that you should be playing," Marshall said. "You hear it from them, but you can't do anything about it because you weren't a free agent or a high draft pick. When Spurrier was here, I wasn't getting anything. No reps, nothing. Then, in the game, I could show them a little something. A lot of it was politics."

Marshall believed he would always be at a disadvantage when it came down to who played and who did not, to who would be allowed to make mistakes and who would never be allowed to feel comfortable by coaches that lacked confidence in them. "You can't play like that," said right guard Chris Samuels. "You can't perform when you have coaches waiting for you to make a mistake so they can give your job to someone else."

Williams tapped into the class rivalries on the Redskins, another motivator for Marshall, who had watched players with higher profiles receive opportunities that were denied him. "When there's a guy who didn't live up to his billing or guys that make the big money that other guys aren't a part of, there's resentment in that room," Williams said. "I took 32 hours of psychology in college and that isn't enough to figure it out."

Blache said that when the coaching staff first began to assess players, Marshall was "at the back of the pack."

"I go back to last year. We didn't know about him from the start and there were question marks about him and about a few other guys," said longtime linebackers coach Dale Lindsey, who coached stars such as Brian Urlacher and Rosevelt Colvin in Chicago and Junior Seau in San Diego. "We didn't know if he was sufficient in talent, toughness and dedication. But Lemar would work hard and prepare himself. Once he got in, he continually got better. He didn't plateau. He's rising all the time."

Williams credits Lindsey's ability to tap into the mind-set of players who felt they had something to prove. Lindsey helped tutor Pierce last season when he emerged as one of the league's top middle linebackers for the Redskins.

"Look at Dale Lindsey's rsum on the people he's coached in the NFL at that position. It's amazing," Williams said. "And even some of the lesser-known guys, how much their careers were molded by being around that tough old bird. I think he brought a lot of that out in Lemar."

Lindsey tends to agree. "We have some guys that this means something to," said Lindsey, a seventh-round draft pick who played nine years in the NFL. "I go back to Antonio and Lemar, guys who come to work to do the job. They're not here to pick up a paycheck. They've got something to prove. People passed them over, didn't want them. They're the downtrodden. They've got a chip on their shoulder, and I'm happy for them because I know what it was like."

It was only after Marshall filled in well for an injured Arrington at outside linebacker last season that Williams began to believe Marshall could contribute as a regular player. "He played his way into his position," Williams said. "During the season last year, he played so well above everyone's expectations, except probably mine or Dale Lindsey's."

When Williams talks about what makes a successful middle linebacker in his system, the first word that comes out of his mouth is toughness. Chris Clemons, the Redskins' reserve weak-side linebacker who routinely replaces Arrington on third-down plays this year, says intelligence is the key. Lindsey says it is awareness. Blache believes it to be conviction.

"You can't be afraid of being wrong," Blache said. "You're making the checks and adjustments for the whole defense predicated on what you see. In other positions, you're just responsible for you. In this one, you're responsible for 10 other guys. Lemar's not afraid to put himself out there in front of 90,000 people with the game on the line, in our case, with our season on the line."

That Marshall excelled in replacing Arrington a year ago gave the coaches confidence that they could expand his role. It did not, however, suggest that Marshall was going to excel at middle linebacker, a more complicated position than the two outside linebackers because he is responsible for his own area as well as the positioning and alignment of the other 10 players. When Pierce left for the Giants during the offseason, the job fell to Marshall.

"One of the things I purposely do, when players ask me questions, I send the players to him. I say, 'Go ask Lemar. He should have those answers.' I purposely feed guys to him," Williams said. "Lemar puts in the time. He has the answers when people ask him the questions."

Lindsey says Marshall is effective at his new position because of his toughness and his ability to react quickly.

"I don't think he's using all of his ability right now. You can see it," Lindsey said. "When he bends his knees and gets in a good football position, he can knock big linemen back off of him. He doesn't do it all the time. If he ever reaches that level where he uses all of his ability all the time, I think it's unlimited what he can do."